bus: fsl-mc: increase MC_CMD_COMPLETION_TIMEOUT_MS value

bus: fsl-mc: increase MC_CMD_COMPLETION_TIMEOUT_MS value

In case the MC firmware runs in debug mode with extensive prints pushed
to the console, the current timeout of 500ms is not enough.
Increase the timeout value so that we don't have any chance of wrongly
assuming that the firmware is not responding when it's just taking more
time.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20250408105814.2837951-7-ioana.ciornei@nxp.com
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>